Water and/or gas meters may be equipped with a rotary disc equipped with a pattern representing a Gray code on two or more bits which, when rotated in front of two or more sensors, enables signals encoded in Gray code on two or more bits to be delivered.
A software program is executed to determine, on the basis of the signals received by the sensors, information on the movement of the disc, particularly its number of revolutions, from which the water or gas consumption can be deduced.
However, the software program is complex, and has become increasingly more so as the number of sensors rises, while they must also be programmable for adaptation to any number of sensors used, and therefore to any number of bits of the Gray code, which further increases their complexity.
This results in, notably, high current consumption, which is problematic when these devices are designed for battery operation.
There is consequently a need to provide a device which is simple to use, with low energy consumption, and permits the simple determination of the movement of a rotary element equipped with a pattern representing a reflected binary code (Gray code) on multiple bits.
There is also a need to provide a device of this type which allows rapid calibration in the factory while being robust against fraudulent acts which aim to reduce the actual value of fluid consumption.